How to Send a Check by Mail: A Step-by-Step Guide

Quick answer: Fill out the check completely, fold it in thirds, and put it in a standard envelope. Address it, add postage, and drop it in a blue USPS collection box or your local Post Office before the last pickup. Prefer to skip the envelope and stamp? OnlineCheckWriter.com’s checks-by-mail feature can print, label, and post a check for you the same business day, if you submit it before the daily cutoff. Delivery after that follows normal USPS or FedEx transit time.

How Do You Send a Check by Mail, Step by Step?

1. Fill in every field. Write the date, the payee’s full name on the “pay to the order of” line, the amount in numbers in the small box, and the same amount spelled out in words on the line below it. If those two amounts do not match, the written words legally control, but many banks’ automated systems will still kick the check to manual review or return it, so read both back before you seal the envelope. A memo line is optional, useful if the payee needs to match your payment to an invoice or account number. See our guide to writing a check for a full walkthrough of each field.
2. Sign it. Match the signature your bank has on file. An unsigned check will not clear.
3. Fold the check in thirds, the same way you’d fold a one-page letter, so the two outer sections meet in the middle. That fits easily into a standard #10 business envelope without adding bulk. Fold a remittance slip or invoice copy to the same size if you’re including one.
4. Place the check inside a standard envelope. Nothing specialized is needed. A window envelope saves you from writing the address twice, since the check shows through the window, but a plain envelope with a handwritten address works just as well.
5. Address both sides. Write the recipient’s full mailing address in the center of the envelope, and your own return address in the top left corner in case it needs to come back to you.
6. Add postage. A First-Class Mail Forever stamp covers up to 1 ounce, enough for a folded check plus a page or two of paper. Going over 1 ounce, or making the envelope more than a quarter inch thick, moves it out of letter pricing into a higher rate. Separately, an envelope that’s square, lumpy, or rigid gets hit with an extra nonmachinable fee, a surcharge USPS charges for anything its sorting machines can’t run automatically. Keep the envelope flat and rectangular to avoid it.
7. Drop the envelope in a blue USPS collection box before the last scheduled pickup, or hand it to a clerk at the Post Office, rather than leaving it in your own mailbox. See the mail theft section below for why that step matters more than any other.

Keep a Mailed Check Safe From Mail Theft

Checks that sit exposed in a mailbox are a common target for theft and check washing, where a stolen check is chemically stripped of its ink and rewritten with a different amount and payee, while your signature is left untouched. Write in dark, permanent ink rather than pencil or a gel pen, since permanent ink is much harder to wash out. The US Postal Inspection Service recommends dropping outgoing mail in a blue collection box before the last scheduled pickup, or handing it directly to a clerk at the Post Office. Don’t leave mail sitting in a home mailbox overnight, including a signed check waiting to go out. Check your incoming mail promptly too, and request a mail hold at the Post Office, or ask someone you trust to collect it, while you’re traveling.

For a check with a meaningful dollar amount, consider USPS Certified Mail instead of a plain stamp. It costs more, but it gives you a receipt and tracking, so you know the check made it rather than just hoping. Businesses that mail checks regularly can also use positive pay, a bank service that flags any check presented with details that don’t match what you issued, which catches a washed or altered check even if it slips past everything above. If you’d rather not print or seal anything yourself, OnlineCheckWriter.com’s check-mailing tool walks through four steps to mail a check online without handling the paper, envelope, or stamp.

What Should You Do if a Mailed Check Never Arrives?

How fast a check arrives depends on the mail class and the distance it travels. USPS lists First-Class Mail delivery at roughly 1 to 5 business days, most of it landing on the shorter end of that range, so give it a reasonable window before assuming something went wrong. If a payee tells you a check never showed up, check your bank account to see whether it has cleared. If it has not, contact your bank about placing a stop payment before you reissue the check. Ask about the fee (commonly $15 to $35) and how long the order lasts: a stop payment you request by phone typically lapses after 14 days unless you confirm it in writing, while a written order usually holds for six months. A stop payment isn’t a guarantee either, it can’t stop a check that’s already been paid, and if the original was chemically altered, a bank matching only on the dollar amount can miss it. That’s part of why certified mail and positive pay, covered above, are worth it for larger checks. Keeping a simple note of what you sent, to whom, and when gives you something concrete to check against either way.

Frequently Asked Questions

Mailing a check by hand is not complicated once you know the sequence: fill it out correctly, fold it to fit, address the envelope both ways, and get it into a collection point instead of an open mailbox. The part most people skip is the last one, and it is the part a stolen or altered check usually comes back to.